Artículos Regulares

Rev. LatinAm. Metal. Mat.2009, 29(1): 3-14

DEFORMATION BEHAVIOR OF MOLYBDENUM SINGLE CRYSTALS AS OBTAINED FROM QUASIRELAXATION IN SITU EXPERIMENTS IN A HIGH VOLTAGE TEM

Pedro Tamayo Meza, Pablo Schabes-Retchkiman, Viacheslav Yermishkin

Online: 29-06-2009

Abstract

A novel methodology for material characterization at the quasi-relaxation regime is presented. The dislocation dynamics on Mo single crystals was studied using experimental relaxation data for two stages of its development. The thermoactivated parameters of dislocation motion in single crystals are fundamental to identify the elementary mechanisms that control dislocation slipping under quasi-relaxation conditions. However, the thermo activated analysis to study the dislocation evolution, is not enough to absolutely identify the process itself. Hence, other methods are required. Thick specimens were tested by in situ HVTEM (High Voltage Transmission Electron Microscopy). As a starting point of non-elastic behavior in the metal, the yield point limit was considered, and modeling in quasirelaxation conditions was developed. Finally, the obtained data and analysis allowed us to reveal that the quasi-relaxation method is a powerful resource to obtain important information about the evolution of dislocations in metals.